Hydraulic door closer



Aug. 22, 1961 E. R. ZIEGLER ETAL 2,996,754

HYDRAULIC DooR CLOSER Filed March 9, 1960 EARL R. Z /E 6l. ER

Raaf/U' A. CARR/ER INVENToRs BY MM2/,WQ

4 r rok/Vey United States Patent Mich.

Filed Mar. 9, 1960, Ser. No. 13,747 Claims. (Cl. 16-52) This inventionrelates to hydraulic door closers and has particular reference to acloser suitable for use on light weight aluminum doors and the like.

An object of the invention is to generally improve devices of thecharacter indicated and to provide a closer which is simple inconstruction, economical to manufacture and efficient in operation.

Another object of the invention is to provide an inexpensive closer,which is effective to resist slamming of the door throughout the greaterpart of the arc through which the door swings.

Another object of the invention is to provide a door closer and doorcheck which is constructed and arranged, so that it may readily beadjusted for uniform closing rate, when used on heavy jalousie typedoors, wooden doors, or light aluminum doors.

Another object of the invention is to provide a device of the characterindicated which is provided with novel means for adjusting andcontrolling the rate of closing.

Another object of the invention is to provide a device which isconstructed and arranged so that it may be operated in any angularposition, either vertical or horizontal.

Another object of the invention is to provide a device of the characterindicated, which -is constructed and arranged to provide a wiping sealfor positive assurance against leakage.

A further object of the invention is to provide a novel means ofassembly whereby su'cient hydraulic fluid can be initially installed toprovide a uniform closing rate through the full travel of the door.`Otherwise the air entrapment, or air pocket, would be great enough topermit slamming of the door during limited openings of the door.

Another object of the invention is to provide a device of the characterindicated which is constructed and arranged with a floating O ringpiston, which provides slight leakage which prevents excessive pressurebuild-up and accommodates dimensional variations in cylinder diameters.Since the outs-ide diameter of the 0 ring 35 is larger than the insidediameter of the tubular member 14, the elasticity of the O ring 35 willpermit dimensional variations in the cylinder diameters without binding,because of the clearance between the O ring 35 and the piston 34.

Another object of the invention is to initially charge the device with ahydraulic Huid, which is compounded to have oxidation stability,rust-inhibiting characteristics, and maintains proper viscosity foroptimum operation during hot or cold weather.

Another object of the invention is to provide means for aixing the valveto the spring while the rod is screwed in or out for adjustment ofclosing speed.

Another object of the invention is to provide resilient means withproper enengy to overcome hydraulic resistance for closing and offeringminimum resistance to opening the door.

Another object of the invention is to provide an end cap assembly whichcloses the end of the cylinder and provides means for mounting the doorcloser so that it may pivot around its longitudinal axis.

The diiculty with inexpensive hydraulic or pneumatic closers or checksis that the door will travel rapidly without resistance for 75 to 80degrees and then abruptly ICC stop, just prior to closing. This can beannoying and dangerous as the door will hit your legs or your back whileopening the inner door, particularly if your arms are loaded withbundles. It is also annoying and dangerous for small children. This typeof closer oiers no resistance to closing when the door is open but a fewdegrees.

It is a further object of the invention to obviate the foregoingdifficulties and .to eiect other advantages, which will appear as thedescription proceeds.

The foregoing and other objects and advantages of the invention Willbecome more apparent as the description proceeds, reference being madefrom time to time from the accompanying drawing forming part of thewithin disclosure in which drawing:

FIG. 1 is a plan view of a device embodying the invention mounted foroperation on a door.

FIG. 2 is =a section taken substantially on the line 2--2 of FIG. l.

FIG. 3 is an enlarged fragmentary view, in section, taken on the line3-3 of FIG. 2, and showing the position of the parts when in closedposition.

FIG. 4 is a view similar to FIG. 3, but showing the position of theparts in open position.

FIG. 5 is a section taken substantially on the line 5--5 of FIG. 2.

Referring now more particularly to the drawing it will be understoodthat in the embodiment herein disclosed the reference characters 7 and 5indicate a conventional, aluminum or wood door and door frame, on whichis mounted the device embodying the invention. The door 7 is providedwith conventional hinges 9 for opening. The device embodying theinvention is pivoted to a bracket 10 secured to the door 7, by metalscrews 11, or other suitable means, and is pivoted to a bracket 12 whichis likewise secured to the frame 8 as at 13.

The device consists of a round tubular member 14, which is closed ateither end by caps 15 and 16. The cap 15 is preferably welded on, as at17 (FIG. 2), and the cap 16 is press fitted on after the end of the tube(FIG. 2) is turned in, as at 18. The inturned end 18 locks in positionan end closure member 19 (FIG. 2), which has a central opening 20 inwhich is positioned a nylon bearing 21 through which extends the pistonrod 22, which also extends through the cap 16 and is pivoted, as at 23,to the bracket 10. The cap 1S has a central opening 15A (FIG. 2) throughwhich extends a stud 24 having an enlarged head 25, which is welded, asat 26, to the inside of the cap 15. The stud 24 has an opening 27therethrough which engages the pivot 13. The free end of the rod 22 isalso provided with an opening 28 which engages the pivot 23.

The end closure member 19 is sealed from the tube 14 by an O ring 29,made of rubber or the like, and is sealed from the rod 22, by a similarO ring 30. A flat rubber wiping seal washer 31, is positioned betweenthe end member 19 and `a metal washer 32, against which abuts one end ofa spring 33, which biases the piston rod 22, and its piston 34. Thepiston 34 is sealed by a iloating rubber O ring 35, and is held againstrotation by means of the end 33A of Ithe spring 33, which is received ineither bore 36 or 42 (FIG. 2), formed in the piston 34. The piston 34 issealed iirom the tubular member 14 by the float-ing rubber O ring 35.The outside diameter of the O ring 35 is slightly larger than the insidediameter of the tubular member 14. The inside diameter of the O -ring 35is larger than the diameter of the ,groove 34A (FIG. 3). This clearanceprovides` a oat between the piston and the O ring. This constructionprovides adequate sealing for low pressure applications, however, if thedoor is forced to close faster than the oil can flow through themetering bores 40 and 41, leakage will occur Patented Aug. Ai172, 1961past the O ring 35 to prevent excessive pressure build-up. This forcedleakage, therefore, prevents damage to the door, the hinges and the doorcloser. The piston 34 is adjustable on the rod 22 by means of aplurality of tine threads 37. This is an important feature of theinvention as it allows the close adjustment of the control valve byturning the rod 22. The piston 34 is preferably a lightweight casting,or screw machine product, and is provided with a large central bore 38,one end of which is counter bored and internally threaded to receive thethreaded end 37 of the rod 22. The bore 38 permits the passage from oneside of the piston 34 to the other of the compounded hydraulic fluid 39,with which -the cylinder 14, is charged. The hydraulic fluid is insertedin the cylinder 14, prior to the insertion of the end closure member 19,the O ring 29 and the O ring 30. This method provides minimum airentrapment or air pockets for optimum smooth performance. The bore 38isin communication with the oifset metering bores 40 and 41, which inturn communicate with the interior of the cylinder 14 on the spring sideof the piston 34. By turning the rod 22 on the line threads 37, the endof the rod opens and closes the openings 40 and 41, to closely controlthe passage of the fluid 39 through the bore 38 from one side of thepiston 34 to the other as shown by the arrows. The two small bores 42and 36 through the piston 34 are opened and closed by a metal washer 43,which serves as a check valve and which is slidably supported on theflared extension 44 formed on the piston 34. As the door 7 is beingopened this washer 43 uncovers the bore 42 and permits the lluid tofreely flow from the spring side of the piston to the opposite side andaround the washer 43 as shown by the arrows (FIG. 4), and when the door7 is being closed the bore 42 is closed and the fluid can only passthrough the central bore 38 and metered openings 40 and 41. With thisconstruction `and arrangement we have complete con trol over the door 7,throughout its full swing in both directions, and the speed of theclosing is easily controlled by turning the piston rod 22.

It is believed that the operation of the device is obvious from theforegoing description.

Having described our invention, what we claim and desire to secure byLetters Patent is:

l. In a door closer, the combination of a tubular member having an endclosure member at each end, and having a hydraulic uid therein, one ofsaid end closure members having an opening therein for receiving apiston rod, a piston secured on said rod, a spring between said pistonand said end closure member having the opening for normally moving saidpiston away from said end closure member having the opening, said pistonhaving an axial passageway extending through the piston, an extension onsaid piston, said extension having a iinely threaded axial bore forreceiving a threaded end of said rod, and communicating with saidpassageway, off set radial bores in said extension in communication withsaid axial bore, said radial bores being arranged to be opened andclosed by the rotation of said rod in said threaded axial bore.

2. The structure of claim 1, in which said piston is sealed from saidtubular member by a oating O ring, and is provided with at least twoauxiliary axial bores, which extend through said piston, a washerslideable on a second extension formed on said piston, said washer beingarranged to close said auxiliary axial bores when the said piston ismoving away from the end closure member with the opening, and open saidauxiliary axial bores when said piston is moving toward said end closuremember with the opening.

3. The structure of claim l, in which there is a bearing support membersecured in the end of said tubular member adjacent to said end closuremember having the opening, a bearing in said support member forslideably receiving said rod, and seals between said tubular member andsaid bearing support member and between said bearing support member andsaid rod.

4. The structure of claim 1, in which the said end closure member havingthe opening is press fitted on said tubular member and said bearingsupport member is secured in position by inturning the end of saidtubular member.

5. The structure of claim 1, in which the end closure member not havingthe opening is rigidly secured to said tubular member and is providedwith a stud adapted to be secured to a door frame, there being anextension on the inner end of said stud inside of said last named endclosure member which serves as a stop for said piston.

References Cited in the le of this patent UNITED STATES PATENTS

